xref: /illumos-gate/usr/src/uts/common/sys/user.h (revision eb6b10e69fa5ba733da194d3ad71a0e63338be29)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
27 /*	  All Rights Reserved	*/
28 /*
29  * Copyright (c) 2018, Joyent, Inc.
30  */
31 
32 
33 #ifndef _SYS_USER_H
34 #define	_SYS_USER_H
35 
36 #include <sys/types.h>
37 #include <sys/signal.h>
38 
39 #ifdef	__cplusplus
40 extern "C" {
41 #endif
42 
43 /*
44  * struct exdata is visible in and out of the kernel. This is because it
45  * is referenced in <sys/core.h> which doesn't have this kind of magic.
46  */
47 struct exdata {
48 	struct vnode	*vp;
49 	size_t	ux_tsize;	/* text size */
50 	size_t	ux_dsize;	/* data size */
51 	size_t	ux_bsize;	/* bss size */
52 	size_t	ux_lsize;	/* lib size */
53 	long	ux_nshlibs;	/* number of shared libs needed */
54 	short	ux_mach;	/* machine type */
55 	short	ux_mag;		/* magic number MUST be here */
56 	off_t	ux_toffset;	/* file offset to raw text */
57 	off_t	ux_doffset;	/* file offset to raw data */
58 	off_t	ux_loffset;	/* file offset to lib sctn */
59 	caddr_t	ux_txtorg;	/* start addr of text in mem */
60 	caddr_t	ux_datorg;	/* start addr of data in mem */
61 	caddr_t	ux_entloc;	/* entry location */
62 };
63 
64 #ifdef	__cplusplus
65 }
66 #endif
67 
68 #if defined(_KERNEL) || defined(_KMEMUSER)
69 
70 #include <sys/param.h>
71 #include <sys/pcb.h>
72 #include <sys/siginfo.h>
73 #include <sys/resource.h>
74 #include <sys/time.h>
75 #include <sys/auxv.h>
76 #include <sys/errno.h>
77 #include <sys/t_lock.h>
78 #include <sys/refstr.h>
79 
80 #ifdef	__cplusplus
81 extern "C" {
82 #endif
83 
84 /*
85  * Entry in the per-process list of open files.
86  * Note: only certain fields are copied in flist_grow() and flist_fork().
87  * This is indicated in brackets in the structure member comments.
88  */
89 typedef struct uf_entry {
90 	kmutex_t	uf_lock;	/* per-fd lock [never copied] */
91 	struct file	*uf_file;	/* file pointer [grow, fork] */
92 	struct fpollinfo *uf_fpollinfo;	/* poll state [grow] */
93 	int		uf_refcnt;	/* LWPs accessing this file [grow] */
94 	int		uf_alloc;	/* right subtree allocs [grow, fork] */
95 	short		uf_flag;	/* fcntl F_GETFD flags [grow, fork] */
96 	short		uf_busy;	/* file is allocated [grow, fork] */
97 	kcondvar_t	uf_wanted_cv;	/* waiting for setf() [never copied] */
98 	kcondvar_t	uf_closing_cv;	/* waiting for close() [never copied] */
99 	struct portfd 	*uf_portfd;	/* associated with port [grow] */
100 	/* Avoid false sharing - pad to coherency granularity (64 bytes) */
101 	char		uf_pad[64 - sizeof (kmutex_t) - 2 * sizeof (void*) -
102 		2 * sizeof (int) - 2 * sizeof (short) -
103 		2 * sizeof (kcondvar_t) - sizeof (struct portfd *)];
104 } uf_entry_t;
105 
106 /*
107  * Retired file lists -- see flist_grow() for details.
108  */
109 typedef struct uf_rlist {
110 	struct uf_rlist	*ur_next;
111 	uf_entry_t	*ur_list;
112 	int		ur_nfiles;
113 } uf_rlist_t;
114 
115 /*
116  * Per-process file information.
117  */
118 typedef struct uf_info {
119 	kmutex_t	fi_lock;	/* see below */
120 	int		fi_badfd;	/* bad file descriptor # */
121 	int		fi_action;	/* action to take on bad fd use */
122 	int		fi_nfiles;	/* number of entries in fi_list[] */
123 	uf_entry_t *volatile fi_list;	/* current file list */
124 	uf_rlist_t	*fi_rlist;	/* retired file lists */
125 } uf_info_t;
126 
127 /*
128  * File list locking.
129  *
130  * Each process has a list of open files, fi_list, indexed by fd.
131  * fi_list is an array of uf_entry_t structures, each with its own lock.
132  * One might think that the correct way to lock a file descriptor would be:
133  *
134  *	ufp = fip->fi_list[fd];
135  *	mutex_enter(&ufp->uf_lock);
136  *
137  * However, that construct is only safe if fi_lock is already held.  If not,
138  * fi_list can change in the window between loading ufp and entering uf_lock.
139  * The UF_ENTER() macro deals with this possibility.  UF_ENTER(ufp, fip, fd)
140  * locks fd and sets ufp to fd's uf_entry.  The locking rules are as follows:
141  *
142  * (1) fi_lock protects fi_list and fi_nfiles.  It also protects the
143  *     uf_alloc and uf_busy fields of every fd's ufp; see fd_find() for
144  *     details on file descriptor allocation.
145  *
146  * (2) UF_ENTER(ufp, fip, fd) locks descriptor fd and sets ufp to point
147  *     to the uf_entry_t for fd.  UF_ENTER() protects all fields in ufp
148  *     except uf_alloc and uf_busy.  UF_ENTER(ufp, fip, fd) also prevents
149  *     ufp->uf_alloc, ufp->uf_busy, fip->fi_list and fip->fi_nfiles from
150  *     changing.
151  *
152  * (3) The lock ordering is (1), (2).
153  *
154  * (4) Note that fip->fi_list and fip->fi_nfiles cannot change while *any*
155  *     file list lock is held.  Thus flist_grow() must acquire all such
156  *     locks -- fi_lock and every fd's uf_lock -- to install a new file list.
157  */
158 #define	UF_ENTER(ufp, fip, fd)					\
159 	for (;;) {						\
160 		uf_entry_t *_flist = (fip)->fi_list;		\
161 		ufp = &_flist[fd];				\
162 		ASSERT((fd) < (fip)->fi_nfiles);		\
163 		mutex_enter(&ufp->uf_lock);			\
164 		if (_flist == (fip)->fi_list)			\
165 			break;					\
166 		mutex_exit(&ufp->uf_lock);			\
167 	}
168 
169 #define	UF_EXIT(ufp)	mutex_exit(&ufp->uf_lock)
170 
171 #define	PSARGSZ		80	/* Space for exec arguments (used by ps(1)) */
172 #define	MAXCOMLEN	16	/* <= MAXNAMLEN, >= sizeof (ac_comm) */
173 
174 typedef struct {		/* kernel syscall set type */
175 	uint_t	word[9];	/* space for syscall numbers [1..288] */
176 } k_sysset_t;
177 
178 /*
179  * __KERN_NAUXV_IMPL is defined as a convenience sizing mechanism
180  * for the portions of the kernel that care about aux vectors.
181  *
182  * Applications that need to know how many aux vectors the kernel
183  * supplies should use the proc(4) interface to read /proc/PID/auxv.
184  *
185  * This value should not be changed in a patch.
186  */
187 #if defined(__sparc)
188 #define	__KERN_NAUXV_IMPL 20
189 #elif defined(__i386) || defined(__amd64)
190 #define	__KERN_NAUXV_IMPL 25
191 #endif
192 
193 struct execsw;
194 
195 /*
196  * The user structure; one allocated per process.  Contains all the
197  * per-process data that doesn't need to be referenced while the
198  * process is swapped.
199  */
200 typedef	struct	user {
201 	/*
202 	 * These fields are initialized at process creation time and never
203 	 * modified.  They can be accessed without acquiring locks.
204 	 */
205 	struct execsw *u_execsw;	/* pointer to exec switch entry */
206 	auxv_t  u_auxv[__KERN_NAUXV_IMPL]; /* aux vector from exec */
207 	timestruc_t u_start;		/* hrestime at process start */
208 	clock_t	u_ticks;		/* lbolt at process start */
209 	char	u_comm[MAXCOMLEN + 1];	/* executable file name from exec */
210 	char	u_psargs[PSARGSZ];	/* arguments from exec */
211 	int	u_argc;			/* value of argc passed to main() */
212 	uintptr_t u_argv;		/* value of argv passed to main() */
213 	uintptr_t u_envp;		/* value of envp passed to main() */
214 	uintptr_t u_commpagep;		/* address of mapped comm page */
215 
216 	/*
217 	 * These fields are protected by p_lock:
218 	 */
219 	struct vnode *u_cdir;		/* current directory */
220 	struct vnode *u_rdir;		/* root directory */
221 	uint64_t u_mem;			/* accumulated memory usage */
222 	size_t	u_mem_max;		/* peak RSS (K) */
223 	mode_t	u_cmask;		/* mask for file creation */
224 	char	u_acflag;		/* accounting flag */
225 	char	u_systrap;		/* /proc: any syscall mask bits set? */
226 	refstr_t *u_cwd;		/* cached string for cwd */
227 
228 	k_sysset_t u_entrymask;		/* /proc syscall stop-on-entry mask */
229 	k_sysset_t u_exitmask;		/* /proc syscall stop-on-exit mask */
230 	k_sigset_t u_signodefer;	/* signals defered when caught */
231 	k_sigset_t u_sigonstack;	/* signals taken on alternate stack */
232 	k_sigset_t u_sigresethand;	/* signals reset when caught */
233 	k_sigset_t u_sigrestart;	/* signals that restart system calls */
234 	k_sigset_t u_sigmask[MAXSIG];	/* signals held while in catcher */
235 	void	(*u_signal[MAXSIG])();	/* Disposition of signals */
236 
237 	/*
238 	 * Resource controls provide the backend for process resource limits,
239 	 * the interfaces for which are maintained for compatibility.  To
240 	 * preserve the behaviour associated with the RLIM_SAVED_CUR and
241 	 * RLIM_SAVED_MAX tokens, we retain the "saved" rlimits.
242 	 */
243 	struct rlimit64	u_saved_rlimit[RLIM_NSAVED];
244 
245 	uf_info_t	u_finfo;	/* open file information */
246 } user_t;
247 
248 #include <sys/proc.h>			/* cannot include before user defined */
249 
250 #ifdef	_KERNEL
251 #define	P_FINFO(p)	(&(p)->p_user.u_finfo)
252 #endif	/* _KERNEL */
253 
254 #ifdef	__cplusplus
255 }
256 #endif
257 
258 #else	/* defined(_KERNEL) || defined(_KMEMUSER) */
259 
260 /*
261  * Here, we define a fake version of struct user for programs
262  * (debuggers) that use ptrace() to read and modify the saved
263  * registers directly in the u-area.  ptrace() has been removed
264  * from the operating system and now exists as a library function
265  * in libc, built on the /proc process filesystem.  The ptrace()
266  * library function provides access only to the members of the
267  * fake struct user defined here.
268  *
269  * User-level programs that must know the real contents of struct
270  * user will have to define _KMEMUSER before including <sys/user.h>.
271  * Such programs also become machine specific. Carefully consider
272  * the consequences of your actions.
273  */
274 
275 #include <sys/regset.h>
276 
277 #ifdef	__cplusplus
278 extern "C" {
279 #endif
280 
281 #define	PSARGSZ		80	/* Space for exec arguments (used by ps(1)) */
282 
283 typedef	struct	user {
284 	gregset_t	u_reg;		/* user's saved registers */
285 	greg_t		*u_ar0;		/* address of user's saved R0 */
286 	char	u_psargs[PSARGSZ];	/* arguments from exec */
287 	void	(*u_signal[MAXSIG])();	/* Disposition of signals */
288 	int		u_code;		/* fault code on trap */
289 	caddr_t		u_addr;		/* fault PC on trap */
290 } user_t;
291 
292 #ifdef	__cplusplus
293 }
294 #endif
295 
296 #endif	/* defined(_KERNEL) || defined(_KMEMUSER) */
297 
298 #endif	/* _SYS_USER_H */
299